Trigger mechanism for firearms



June 8, 1943. w. c. Rox-:MER 2,321,044

TRIGGER-MECHANI SM FORy FIREARMS Filed Jan. 18, 1940 4 Sheets-Sheet 1 W. C. ROEMER TRIGGER-MECHANI SM FOR FIREARMS June 8, 1943.

4 Sheets-Sheet 2 Filed Jan. 18, 194'.

June 8, W. C. TRIGGER-MECHANISM FOR FIREARMS Filed Jan. 18, 1940 4 Sheets-Sheet 5 `Tune 8, 1943. w. c. ROEMER 2,321,044

TR IGGERMECHANISM FOR FIREARMS Filed Jan. 18, '1940 4 Sheets-Sheet 4 @SIMS Patented l.tune 8, 1943 UNETE ST'ES 2,321,044 TRGGER MECHANISM FR FIREARMS Application January 18, 1940, Serial No. IJAAZE (Cl. i23) 1 Ciaim.

This invention relates to improvements in trigger-mechanisms for rearms and more particularly to trigger-mechanisms for that type of firearm wherein the breech-bolt is moved rearwardly by an action-slide or the like for the ejection of a fired cartridge and the insertion of a fresh cartridge into the cartridge-chamber of the firearm.

One of the objects of the present invention is to provide a rearm having a superior construction and arrangement of parts whereby the trigger is automatically uncoupled from the sear immediately upon the breech-bolt being unlocked and prior to the cooking of the firing-mechanism, the said trigger remaining uncoupled from the sear during the rearward and forward travel oi the breech-bolt until the latter has returned to its breech-closing position.

Another object of the present invention is to provide a superior trigger-mechanism having means interposed between the trigger and the sear for coupling the trigger to the sear and so constructed and arranged as to permit the sear to be moved into its cooking position immediately following the discharge of the iirearm.

A further object of the present invention is to provide a superior trigger-mechanism having means constructed and arranged to uncouple the trigger from the sear to permit the sear to be moved into its cooking position even in the event of the trigger being held in its firing position so that the firearm cannot be again discharged save upon the release and subsequent actuation oi the trigger for each shot.

Still another object of the present invention is to provide a superior trigger-mechanism having coupling-means incorporated therein and mounted in such manner as to have movement substantially-parallel to the travel of the actionslide for coupling and uncoupling the trigger and the sear.

A still further object of the present invention is to provide a superior trigger-mechanism so constructed and arranged as to prevent the safety-device of the rearrn from being moved into its safe position prior to the cooking of the firearm.

With the above and other objects in View, as will appear to those skilled in the art from the present disclosure, this invention includes all features in the said disclosure which are novel over the prior art and which are not claimed in any separate application.

In the accompanying drawings, in which certain modes of carrying out the present invention are shown for illustrative purposes:

Fig. l is a broken view mainly in side elevation and partly in vertical central-longitudinal section of the rear portion of a firearm embodying the present invention, the breech-bolt being shown in its breech-closing position;

Fig. 2 is an enlarged view partly in vertical central-longitudinal section and partly in side elevation of the portion of the firearm at and adjacent the trigger-mechanism, the hammer being shown in its cocked position preparatory to the discharge of the iirearm;

Fig. 3 is a view corresponding to Fig. 2 but showing the parts in the positions which they assume when the breech-bolt has been moved rearwardly into its retired position and with the trigger held back in its firing position;

Fig. 4 is a fragmentary horizontal view taken on the line 4 4 of Fig. 2;

Fig. 5 is a fragmentary transverse view taken on the line 5--5 of Fig. 2;

Fig. 6 is a transverse sectional view the line li--B of Fig. 2;

Fig. 7 is a transverse sectional view taken on the line 'i--l of Fig. 2;

Fig. 8 is a perspective view of the trigger detached;

Fig. 9 is a perspective view of the sear;

Fig. 10 is a perspective view of the bell-cranklike shifter together with the transmitting-member carried thereby;

Fig. 11 is a perspective View of the transmittingmember;

Fig. 12 is a broken perspective view of the rear portion of the action-slide looking mainly at the underside thereof; and

Fig. 13 is a perspective view of the hammer.

The firearm herein chosen for illustrating the present invention includes a receiver l5, a barrel IB, a receiver-extension l1, a trigger-plate I8 and a stock i9. The barrel l5 extends forwardly from the said receiver I5 and is secured thereto in the usual manner of rearms and the receiver-extension l'l extends rearwardly from the said receiver and serves to couple the latter firmly to the stock i9.

The receiver l5 includes a top-wall 29 from the respective opposite sides of which depend two laterally-spaced-apart side-walls 2|-2l providing a mechanism-receiving chamber 22 in which a breech-bolt 23 is adapted to be tilted and reciprocated by an action-slide 24. The actionslide 24 reciprocates longitudinally of the rearm Vand may be moved rearwardly in any suitable sectional sectional taken on manner, such, for instance, as by a gas-operated piston, as is shown in my co-pending application Serial No. 313,650, filed January 13, 1940.

The reciprocating breech-bolt 23 just above referred to, has pivotally coupled t its rear end by means of a pivot-pin 25, the upper end of an operating-link 26 which latter is also pivotally secured at its lower end by a pivot-pin 21 to a cross-head 28 forming a feature of the actionslide 24 before referred to. The cross-head 28 of the action-slide 24 has welded, brazed or otherwise secured to its respective opposite sides the rear ends of two parallel spaced-apart side-bars 29-29. The side-bars 29-29 of the action-slide 24 are held in laterally-spaced relationship by the cross-head 28 and extend forwardly therefrom with capacity for longitudinal reciprocating movement.

Extending rigidly rearwardly from the crosshead 28 of the action-slide 24 is a stem 38 bearing at its rear end against the forward end of a spring plunger 30a (Fig. 1) mounted with capacity for reciprocating movement in the receiver-extension I1 before referred to, and which is constantly urged forwardly by a breech-boltreturn spring 3| (Fig. 1).

'I'he side walls 32-32 of the trigger-plate I8 are laterally-spaced-apart to provide a longitudinal clearance-groove 33 in the trigger-plate I8, which latter may be secured to the underside of the receiver I in any suitable manner. From the upper edges of the side walls 32--32 just referred to, respectively upwardly project ears 34-34 (Fig. 6) serving to support the respective opposite ends of a pivot-pin 35 pivotally mounting a hammer 36 between the said ears 34--34.

The hammer 36 is formed in its rear face with a longitudinal clearance-passage 31 into which extends the forward end of a hammer-actuating plunger 38 pivotally secured by a pivot-pin 39 to the said hammer 36. The hammer-actuating plunger 38 includes a spring-guiding stem 4|] mounted at its rear for sliding movement in a transversely-extending abutment-member 4I located in the clearance-groove 33l of the triggerplate I8 and pivotally supported at its respective opposite ends in the side walls 32-32 of the said trigger-plate. Encircling the forward portion of the stern 48 and interposed between the forward face of the abutment-member 4I and a rearwardly-facing shoulder 42 formed on the plunger 38, is a helical hammer-spring 43. The opposite ends of the said hammer-spring 43 respectively thrust against the forward face of the abutmentmember 4I and the shoulder 42 of the plunger 38 to constantly urge the hammer 36 forwardly to strike a firing-plunger 44 carried by the breech-bolt 23, to effect the discharge of a cartridge.

To enable the hammer 36 and the forward portion of the hammer-actuating plunger 38 to swing upwardly and forwardly under the urge of the hammer-spring 43 to effect the discharge of the firearm, the action-slide 24 is provided with a longitudinal clearance-slot 45. The said clearance-slot is formed partly in the stem 38 and partly in the cross-head 28 of the action-slide 24. The hammer 36 is located in the said clearance-slot 45 when in its cocked position.

The trigger-plate I8 is formed with the usual integral loop-like trigger-guard 46 which encloses the linger-piece 41 of a trigger 48 carried by the said trigger-plate I8. The major portion of the trigger 48 is located in the clearancegroove 33 of the said trigger-plate I8 and is mounted for pivotal movement upon a pivot-pin 49 extending transversely of the said triggerplate with its respective opposite ends supported in the side-walls 32-32 thereof, as is shown in Fig. 5. The finger-piece 41 of the trigger 48 extends downwardly through a vertical clearanceslot 50 formed in the said trigger-plate I8 and leading downwardly from the clearance-groove 33 therein to the under face of the said triggerplate.

The trigger 48 is formed with two laterallyspaced-apart forwardly-extending parallel arms 5I-5I united at their forward or outer ends by an integral bridge 52 for the purpose as will hereinafter appear. The central portion of the said trigger 48 is formed with a longitudinal clearance-groove 53 across which the pivot-pin 49 of the trigger 48 extends. Located in the clearance-groove 53 of the trigger 48 is the rear end of a sear 54 mounted upon the pivot-pin 49 just referred to, for independent pivotal movement with respect to the said trigger 48.

The sear 54 extends forwardly between the arms 5I-5I of the trigger 48, with its forward portion passing beneath the bridge 52 of the said trigger, as is clearlyl shown in Figs. 2 and 3. Formed on the upper edge of the sear 54 about midway of its length is a forwardly-facing cocking-shoulder 55 adapted to engage a rearwardlyfacing cooking-abutment 56 forming one face of a cooking-notch 51 provided in the hammer 36. The sear 54, by the engagement of its cookingshoulder 55 with the cooking-abutment 56 of the hammer 36, serves to releasably maintain the said hammer in its cocked position against the tension of the hammer-spring 43 until such time as the cooking-shoulder 55 is moved downwardly out of engagement with the cooking-abutment 56 of the hammer 36 by the actuation of the trigger 48, al1 as will more clearly hereinafter appear.

Immediately to the rear of the cooking-shoulder 55 the sear 54 is formed on its upper edge with an arcuate abutment 58 adapted to be engaged with the arcuate outer face of a lug 59 forming that portion of the hammer 36 immediately forwardly of the cocking-notch 51 formed therein. The arcuate outer face of the lug 59 is concentric with the center of the pivot-pin 35 of the said hammer 36. The lug 59 of the hammer 36 serves, when engaged by the arcuate abutment 58 of the sear 54, to retain the said sear in its depressed or hammer-releasing position for the purpose and in a manner as will hereinafter appear, until such time as the hammer 36 is again cocked after the actuation of the trigger 48 and the swinging of the said hammer to effect the discharge of the firearm.

The sear 54 is provided intermediate the pivotpin 49 and the cocking-shoulder 55 thereof with a downwardly-opening spring-pocket 6U in which is located the upper portion of a helical scar-spring 6I having its lower end seated against the adjacent bottom of the clearancegroove 33 in the trigger-plate I8. The searspring 6I exerts a constant but yielding effort to move the sear 54 upwardly into position to interpose its cooking-shoulder 55 in the path of movement of the cooking-abutment 56 of the hammer 36. At its forward end the sear 54 is formed with a downwardly-and-forwardly-extending nger 62 which normally is positioned over and in registration with a notch 63 provided in a safety-slide 64.

The safety-slide 64 is mounted for axial shift- Iing movement in a passage 65 extending transversely of the tripper-plate I8 in the forward portion thereof adjacent the space enclosed by the trigger-guard 45 of the said trigger-plate as is clearly shown in Figs. 2, 3 and 7. The safetyslide 54 is adapted to be axially shifted in the passage E5 into either its safe position or firing-position as is usual with safety devices. It will be understood that by Yaxially shifting the safety-slide 64 into its safe position that the notch 53 therein will be moved out of registration with the finger 62 of the sear 54 and that by being so shifted, a portion 63 adjacent the said notch 63 forming a peripheral part of the said safety-slide, will be moved beneath the under edge of the ringer G2 of the sear 54 to thus prevent the said sear from being moved downwardly for the release of the hammer 35. By shifting the said safety-slide into its firing-position the notch 53 therein will be in the position shown in the drawings, and the sear 54 may be moved downwardly in a manner as, Ywill hereinafter appear, thus entering the nger 62 thereof into the notch B3 of the said safety-slide without interference thereby when the trigger 48 is actuated to effect the discharge of the firearm.

For the purpose of coupling he trigger 48 to the sear 54 and uncoupling the same therefrom to transmit the swinging movement of the said trigger to the sear 54, the trigger-plate i3 forwardly of the hammer 36, pivotally carries a shifter 67 of bell-crank-like form. The shifter G7 is mounted for pivotal movement on a pivotpin 63 extending transversely of the said triggerplate i8 across the upper forward portion of the clearance-groove 33 therein, and which is supported at its respective opposite ends in the respective side walls 32-32 of the said triggerplate i8 as is clearly shown in Figs. 4 and 7. The shifter 61 has its depending arm 69 formed in its lower end with a longitudinal clearance-groove lll, in which is located the forward 01 inner end of a horizontally arranged pivotal transmittingmember 1I.

The transmitting-member "il just above referred to, is lmounted for free rocking movement relative to the shifter 61 upon a pivot-pin l2 having its opposite ends respectively supported in ears 'I3-13 formingV the respective side walls of the clearance-groove 'l0 in the depending arm 69 of the shifter 61. The transmitting-member 'H extends rearwardly substantially-horizontal- 1y and is adapted to have its substantially-cylindrical outer or rear end 'i4 normally located between the under face of the bridge 52 of the trigger-48 and the upper edge of the sear 54, as is clearly shown in Figs. 2 and 3.

Intermediate the pivot-pin B8 and the transmitting-member 1l, the depending arm 69 of the shifter 61 is provided with a forwardly-opening spring-pocket 15 housing a `helical spring 16 which thrusts against the adjacent forward endwall of the clearance-groove 33 in the triggerplate I8. The horizontal arm ll of the Sear-actuator 6l carries at its rear or free end a relatively-long cam-pin 18 extending transversely through the said arm ll with each of its respective opposite ends normally `disposed in the adjacent one of two clearance-notches rifi-'i9 respectively formed in the under edge of the adjacent rear portion of the side-bars 2li-29 of the action-slide 24 when the Vlatter is in its forward position.

The spring 'I6 above referred to constantly urges the shifter 61 to turn in a clockwise direction as viewed in Figs. 2 and 3, to maintain the cylindrical end 14 of the transmitting-member 1| interposed between the bridge 52 of the trigger 48 and the `sear 54, for the purpose as will hereinafter appear. The spring 16 also serves to urge the opposite ends of the campin 'I8 respectively upwardly into the clearancenotches 'F9-'i9 ofthe action-slide 24 `for engagement by forwardly-and-downwardly-inclined uncoupling-cams 8th-80, each of which forms the forward wall of one of the clearance-notches 'l-1S.

The uncoupling-cams 8-83 are adapted to engage the adjacent opposite ends of the campin 'I3 as just above referred to, when the action-slide 24 is moved rearwardly, to rock the shifter 6l' in a counterclockwise direction from the position in which it is shown in Fig. 2 into that shown in Fig. 3. This counterclockwise turning of the `shifter 6l will serve to swing the depending-arm 69 thereof forwardly and hence withdraw the cylindrical end T4 of the transmitting-member 'll secured thereto out from between the bridge 52 of the trigger 48 and the scar 54, the said transmitting-member assuming the position in which it is shown in Fig. 3. The described counterclockwise turning movement of the shifter 61 will be effected against the tension of the spring 'IE which holds the respective opposite ends of the cam-pin 18 in engagement with the lower edges of the adjacent side-bars 25-29 of the action-slide 24 during the major ypart of its rearward and forward travel. The retention of the vcam-pin 18 as just described prevents the said shifter from turning clockwise until the action-slide 24 has reached its forward position and the clearance-notches 'IB-19 of the said action-slide are again in registration with the opposite ends of the said cam-pin 1B.

To hold the trigger 48 in its normal position, the saidtrigger is formed adjacent its ngerpiece 4'! -with an upwardly-and-rearwardlyinclined spring-pocket 8l opening through the rear upper edge thereof and receiving a springplunger '82 having a guide-stem 83 encircled by a helical trigger-spring 84. One end of the trigger-spring 84 thrusts against the end wall of the spring-pocket 8l while the opposite end thrusts against the adjacent face of the springplunger '82 to thus hold the said spring-plunger in seated engagement with the adjacent portion of the trigger-plate I8 and thus hold the trigger 43 in its normaler non-firing position.

For the purpose of description, let it is assumed that the cartridge-chamber of the nrearm contains a cartridge and that the hammer 36 is cocked and the associated parts are in their respective positions in readiness for the discharge of the firearm, as shown in Figs. l and 2. Under this condition, the breech-bolt 23 is in its breech-closing position, and the action-slide 24 is in its full forward position. The safety-slide 54 will, when the firearm is in readiness for firing, be in its firing-position, i. e.. in position wherein its notch 63 is in full registration with the nger 62 of the sear 54.

If rearward draft is now applied to the ngerpiece 4T of the trigger 48 to rock the said trigger clockwise about its pivot-pin 49 against the tension of the trigger-spring B4, the forward ends of the arms 5|-5I of the said trigger will be swung downwardly. This downward movement of the forward ends of the said arms 5I--5I of the trigger 48 will cause the `bridge 52 therebetween Yto correspondingly move the cylindrical end 'I4 of the transmitting-member 1| downwardly. Owing to the position of the cylindrical end 14 of the transmitting-member 1| over the sear 54, it will be readily apparent that any downward rocking movement of the said transmitting-member about its pivot-pin 12 will cause the outer or forward end of the said sear 54 to be concurrently moved downwardly against the tension of the sear-spring 6| to thus withdraw the cooking-shoulder 55 of the said sear from its engagement with the cooking-abutment 56 of the hammer 36. The withdrawal of the cocking-shoulder 55 of the sear 54 as just described will enable the hammer 36 to be rapidly swfung in a Iclockwisel direction into the position indicated by broken lines in Fig. 2, under the urge of the hammer-spring 43. The hammer 36 near the completion of its clockwise turning movement under the urge of the hammer-spring 43, will sharply strike the rear eX- posed end of the firing-plunger 44 to snap the latter'forwardly to discharge the cartridge contained in the cartridge-chamber of the rearm in a manner well understood in the art.

When the trigger 48 is actuated as just above described, to effect the downward movement of the sear 54 for the release of the hammer 36, the finger 62 of the said sear is entered into the notch 63 of the safety-slide 64 when the said safety-slide is in its ring-position, in which position the said safety-slide is shown in Fig. 7. When the sear is in its depressed or hammerreleasing position and the hammer 36 swings in a clockwise direction to effect the discharge of the firearm, the lug 59 thereof will override the arcuate abutment 58 of the sear 54.

With the lug 59 of the hammer 36 in engagement with the arcuate abutment 58 of the sear 54 when the hammer is in its firing-position as shown by broken lines in Fig. 2, the sear 54 will be held in its down position against the tension of the sear-spring 6| with the lower end of its finger 62 entered into the notch 53 of the safetyslide 64. It will be apparent from the foregoing that with the lower end of the nger 62 of the sear 54 entered into the notch 63 of the safety-slide 64, the latter is prevented from being axially shifted into its safe position by the finger 62 of the said sear until such time as the said finger 62 is retired upwardly from the notch E3 of the said safety-slide. In this manner the safety-slide 64 -i'is prevented from being axially shifted into its safe position until the hammer 36 has been swung in a counterclockwise direction into its cocked position. When the hammer 36 is in its cocked position, the lug 59 thereof is removed from over the arcuate abutment 58 of the sear 54, thus freeing the said sear for movement upwardly into its cocking-position under the urge of its searspring 6|. It will be understood that with the hammer swung rearwardly and with the sear 54 in its cooking or hammer-retaining position and its finger 62 removed from the notch 63 in the safety-slide 64, the said safety-slide may be axially shifted into its safe position to bring its portion 66 beneath the nger 62 of the said sear to thereby prevent the downward swinging movement of the sear 54.

It will be apparent from the foregoing that the sear 54 is held in its depressed position by the hammer 36 during the major portion of the latters swinging movement in both clockwise and counterclockwise directions. The said sear is released for upward movement only when the said hammer is in its retired position as shown in Figs. 2 and 3. 'Ihe safety-slide is thus prevented from being either unintentionally or deliberately axially shifted into its safe position. In preventing the safety-slide 64 from being axially shifted into its safe position when the hammer is in its firing position as shown by broken lines in Figs. 2, the possibility of serious damage to the trigger mechanism is avoided, since the hammer and sear are free to move into their respective cocked and hammer-retaining positions without interference on the part of the safety-slide.

Following the discharge of the firearm, the rearward movement of the action-slide 24 will eilect the unlocking and rearward movement of the tilting and reciprocating breech-bolt 23 to cause the ejection of the just-fired cartridge. This rearward movement or travel of the actionslide 24 will cause the uncoupling-cams BIJ- B8 of the said action-slide to respectively engage the respective opposite ends of the cam-pin 18 now located notches 19-19 immediately upon the start of the rearward travel of the said action-slide 24. The uncoupling-cams 88-80 upon engaging the respective opposite ends of the campin 18 will cam the latter downwardly to thus swing the shifter 61 in a counterclockwise direction against the tension of the helical spring 16, into the position shown in Fig. 3.

The counterclockwise movement as above described, will swing the lower end of the depending-arm 69 of the shifter 61 forwardly to thus correspondingly shift the transmittingmember 1| to remove the cylindrical end 14 thereof from between the bridge 52 of the trigger 48 and the sear 54, thus releasing the said sear for upward movement. The withdrawal of the transmitting-member 1| from between the bridge 52 of the trigger 48 and the sear 54 will uncouple the two said elements and will permit the sear-spring 6| to assert itself to swing the sear 54 upwardly into position to enable its cocking-shoulder 55 to be re-engaged by the cooking-abutment 56 of the hammer 36 when the said hammer is swung into its cocked position by the rearward movement of the action-slide 24.

The hammer 36 is swung into its cocked position, when the action-slide 24 moves rearwardly, by a portion of its cross-head 28 which engages the forward face of the hammer 36 to swing the said hammer in a counterclockwise direction against the tension of the hammerspring 43.

During all but the initial rearward travel of the action-slide 24, the respective opposite ends of the cam-pin 18 are in engagement with the respective lower edges of the side-bars 29-29 of the action-slide 24. This engagement temporarily prevents the shifter 61 from again assuming the position in which it is shown in Fig. 2, and thus serves to hold the cylindrical end 14 of the transmitting-member 1| out from between the bridge 52 of the trigger 48 and the sear 54 as shown in Fig. 3, until such time as )the clearance-notches 19--19 of the actionslide 24 are again respectively brought in registration with the opposite ends of the cam-pin 18 by the full return movement of the actionslide 24.

By preventing 'the transmitting-member 1| from entering the space between the bridge 52 of the trigger 43 and the upper edge of the sear 54 in their respective clearanceuntil such time as the action-slide 24 is fully returned to its forward position, the scar 54 is rendered immune during this time interval against being again swung downwardly by any movement of the trigger 48. It will be understood that with the transmitting-member 'll in the position shown in Fig. 3 with its cylindrical end 'i4 removed from between the bridge 52 of the trigger i8 and the sear 54, the said sear is free to be moved upwardly into its hammer-retaining position immediately following the actuation of the trigger 43 under the urge of the Sear-spring 6| for reengaging the hammer 36.

From the foregoing it will be apparent that substantiallyimmediately following the initiation of the rearward movement of the action-slide 24, the shifter 51 is so moved as to render the transmitting-member 1| inoperative until such time as not only has the said action-slide been returned to its full forward position, but rearward draft upon the trigger 43 has been relaxed. In this manner the sear 54 is free to move upwardly immediately following the discharge of the firearm so that it may be in position t retain the hammer 3'5 in its cocked position. Furthermore, the repeated discharge of the firearm is prevented until suc-h time as the operator of the firearm has relaxed rearward draft upon the trigger 48, and the action-slide 24 as well as the breech-bolt 23 have been returned to their full forward position.

In the event that it is desired to remove an unred cartridge from the firearm, this may be effected by rearwardly moving the action-slide 24 to effect the retiring of the breech-bolt 23 without regard to the trigger 48. During this operation, however, the shifter G1 will be swung in a counter-clockwise direction to thereby remove the transmitting-member 'll to effectively uncouple the trigger 1,8 from the sear 54 `and thus guard against the release of the hammer 36 during this operation.

By the construction and arrangement of parts herein shown and described, a compact triggermechanism, durable and reliable in its operation, may be readily manufactured. Furthermore, the arrangement of parts is such as to prevent the action-slide, in the event of damage to or the jamming of the trigger-mechanism, from disengaging the sear from the hammer 36 upon the rearward movement of the said action-slide. It will be noted that as the action-slide moves rearwardly, it institutes a forward movement of the transmitting-member 'll which is substantiallyparallel with the surfaces between which it is interposed rather than a perpendicular movement, in withdrawing the said transmitting-member from its position between the trigger 48 and the sear 513.

It will be further apparent that by means 0f the construction herein shown and described, the

safety-slide is rendered inoperable save only at such time as the hammer is in its retired position, thereby guarding vagainst the shifting of the said safety-slide when the hammer is in its firing position.

The invention may be carried out in other specic ways than those herein set forth without departing from the spirit and essential characteristics of the invention, and the present ernbodiments are, therefore, to be considered in all respects as illustrative and not restrictive, and all changes coming within the meaning and equivalency range of the appended claim are intended to be embraced therein.

I claim:

A firearm-structure including in combination: a frame; a first pivot extending crosswise of the frame; a swinging hammer swinging around the said first pivot; a second pivot located to the rear of the said first pivot and in substantial parallelism therewith; a sear swinging around the said second pivot and extending forwardly therefrom beyond the said first pivot and provided adjacent its forward end with an upwardlyfacing actuating surface, the said sear coacting intermediate its ends with the said hammer to releasably hold the latter in its cocked position; a trigger swinging around the said second pivot and provided with two laterally-spaced-apart side-walls embracing the sides of the said Sear and with a downwardly-facing actuating-surface located forwardly of the said first pivot and over the upwardly-facing actuating-surface of the said Sear;- a third pivot located forwardly of the said rst pivot and second pivot; a bell-crank-shaped shifting-lever swinging intermediate its ends around the said third pivot and comprising a rearwardly-extending arm having cam-engaging means and .a downwardly-extending arm; a transmitting-member pivoted at its forward end to the downwardly-extending arm of the said shifing-lever and normally extending rearwardly between the respective actuating-surfaces of the said sear and trigger to transmit the movement of the latter to the former; a breech-bolt; and an action-slide reciprocating lengthwise of the frame and operatively connected to the said breech-bolt and provided with a cam-surface engageable with the cam-engaging means of the rearwardly-extending arm of the said shiftinglever at a point forwardly of the said first pivot and rearwardly of the said third pivot and constructed and arranged to depress the said downwardly-extending arm of the shifting-lever and thereby withdraw the rear portion of the said transmitting-member from between the respective actuating-surfaces of the said Sear and the said trigger.

WILLIAM C. ROEMER. 

